A couple of
years ago, I landed an internship at the Goddard Space Flight Center in Greenbelt, Md. with a mission: to help finish the design, construction and testing of
a prototype "dust mitigation vehicle".
I couldn't
wait to get started, but I had a few questions -- what exactly is a "dust
mitigation vehicle," and why would we need one?
The
"why" is pretty surprising. During the
Apollo program, lunar dust (or "regolith" as the geologists like
to call it) proved to be a significant challenge. Apollo 17 astronaut Gene Cernan
even went as far as to say, "I think dust is probably one of our greatest
inhibitors to a nominal operation on the moon. I think we can overcome other
physiological or physical or mechanical problems except dust."
The
fine-grained particles wore through the outer layer of astronauts' spacesuits,
caused seals to leak, scratched visors and even affected astronauts' health
with breathing issues. Whenever the regolith so much as touched a piece of equipment,
astronauts found it nearly impossible to clean.
Those are a
just a few reasons why lunar dust is so problematic.
As Ryan
mentioned in his September
25th blog entry, it is extremely abrasive, meaning that it is able to
scratch most things with which it comes into contact. I suppose I'd compare it
to ground-up shards of glass. To make matters worse, the dust is statically
charged. If you've ever rubbed a balloon on your head, you can wave the balloon
over pepper grains to make them cling to it. Same concept with moon dust,
except that instead of pepper the astronaut attracts microscopic, razor-sharp
particles.
No
surprise, then, that NASA spends a lot of time and resources to find ways to
both prevent dust from getting on equipment and to remove it if necessary.
The Dust
Mitigation Vehicle (or “DMV”) that I worked on is one of these methods. It's a
prototype of a rover that would pave the surface of the Moon. It doesn't use
asphalt or concrete, but rather sunlight -- something of which we have a nearly
unlimited supply on the moon!
The DMV is
essentially a rover with a giant converging lens mounted to it. Ever used a
magnifying glass to burn leaves (or even poor, defenseless ants) during the
summer? Again, same concept.
The vehicle's
lens tightly focuses sunlight on area ahead of the vehicle, causing the
regolith to reach temperatures well above 3,000 degrees Fahrenheit -- this heat
melts the moon dust into a hard, dust-free surface. Run the DMV long enough,
and you can create roads or even landing pads. When astronauts or other rovers
travel on these hardened areas, they would no longer kick up dust.
I hope that
some day vehicles similar to the DMV traverse the surface of the Moon and build
roads as they go. If that doesn’t happen, I suppose I could open my own chemical-free
ant extermination business. Either way, working on this project has been
personally rewarding -- and a lot of fun.
Brandon Hall is an aerospace engineering undergraduate
student at the University of Maryland, College Park. He has conducted research
with NASA Goddard Space Flight Center focused primarily on In-Situ Resource
Utilization.
Photos:
Courtesy of Brandon Hall/NASA
Captions, top to bottom:
- Overseeing
DMV operation. I'm using welding goggles to protect my eyes from the intense
focused sunlight.
- The Dust
Mitigation Vehicle with the large Fresnel lens clearly displayed
- Partially
and fully “paved” samples.
- A profile
shot of the DMV.
Recent Comments